Cutting chain sharpener



May 4, 1943.

A. N. BLUM 2,318,456

CUTTING CHAIN SHARPENER Filed Dec. 30, 1939 4 Sheets-Sheet l May 4, 1943.

A. N. BLUM 2,318,456

CUTTING CHAIN SHARPENER 4 Sheets-Sheet 2 May 4, 1943. A. N. BLUM 2,318,456

CUTTING CHAIN SHARPENER Filed Dec. 30, 1959 4 Sheets-Sheet 3 y 1943- A. N. BLUM 2,318,456

CUTTING CHAIN SHARPENER Filed Dec. 30. 1939 4 Sheets-Sheet 4 Patented May 4, 1943 waist UN T E D i STATES "PATENT :QF-E 1Q E CUTTINGCHAIN SHARPENER vArtlmrlN; Blum, Philadelphia; Pa.

" Application December 4 1 25 Claims.

This invention relates to devices for sharpening-cutterteeth, and while the principles of the invention; as hereinafter defined, may be used to advantage-indevices for sharpeningthe cutting teeth of a varietyof -tools, -the'immediate' object is to provide an improved-device for I sharpening the teeth of chain-saws.

- More specifically, an object of the invention is e to provide a device of the stated character having the extreme flexibility of adjustment to permit presentationof the work to the sharpening-tool in any relative-position that maybe required' to efiect the proper sharpening of the individual teeth and wherein provision is made for the precise positioning of each tooth with respect tothe sharpeningtool that is essential for obtaining exact. uniformity i in the corresponding teeth of the entire series.

--Another-object of the invention isto-provide a sharpening device of the stated character in the nature of an attachment that shall be capable of application to commercial grinders ofconven- -tional form.

'Ihe invention iurther resides in-various struc- --tural and mechanical details hereinafter de scribed and illustrated in the attached drawings, -in-whichz --Figure 1' is a viewin perspective. of a device made in accordance with my invention;

--Fig-. 2 is a rear view inperspective'of one of theelements of the device shown in Fig. l;

Fig. 3 is a fragmentary'front elevational-view illustrating a detail of construction;

' Fig. 4 is an enlarged side-elevationalwi'ew of a the device;

Fig. 5 is a sectional view taken onthe line 5-5, Fig. 4; :Fig. 6 is a sectional view taken onthe'line 5-6, Fig. 5;

Fig. 7 is a view in perspective of. one? ofthe elements of the device'shown in :Fig; 5;

Fig. 8 is a sectional view taken-'on the -line i 3 -8 -Fig. 4;

V :Fig. 9 is a sectional view taken on" the line 9, Fig. l;

illustrating themode of operation of one of 'the elements of =-the device;

Fig; 1 3 is a fragmentary sectional viewillustrating the relative positions of the work and -the -sharpening--tool during the sharpening operation Figifhln is airagmentary side elevational View 'illustrating armodification within the, scope of the invention;

Fig; is a corresponding view showing; the

5. villustratedjelementsin a"ctifferent' position of 'relative'adjustment;

f Fig; 17 is a'jviewinperspectiveofonecf the "10 elements,of'the;v device; illustrated in. the immefdiately preceding figures.

With. reference to'the' drawings; thereference numeral lld'esignates, a pedestal supportfor a ,.commercialgrindeii 2,i the said grinder being "'15 fizfedto said .supp'orthy bolts The. grinder 2 J comprises the, usual. housing infer ,an gelectric motorftheushaftj 5 fof 1' this, motor projecting through-opposite sides of the housing and having attached to the respective: projecting endsabra- 20 .sive,wheels 6 .and. 1. "lfhejabrasivezwheel l in I the present instance is of a special form designed i for:grinding:;the t'ei'etl fof a; chain saw "Of the character to'iwhich the present invention relates.

.i IAtt'ached to the ,fixed1 .struct ure"of the grinder 2 is a guard a, andsua d s mou t i'a the conventional manner; io1 angular. adjust- ..mentgaboutthmaxisjofithej shaft 5.: In the i present instancethe guard. is adjustably fitted v to;the cylindrical extensionflilof the housing i I 30.iniWhich the' ishatt 5jof the motor is journaled, e and is anchoredin'adjiistedpcsition on said extension by means of thefsplit-jcollarclamp shown at Ba in'Fig. 2TT1'Ihc guard 8 is;.pr qvidedwith an aperturedi boss 9., see Fig, 3,.i-which is shaped for interlockinglslidingnengagement with a slotted iarm' ll of a bracket 12;; The arm ll is channeled relongitildinallyiorvreceptioniof the boss 9, and the. latter acts as aguide for adjustment of the ..-.arm on theigua'rdlinthe longitudinal direction.

" 40 A b.0ltl3 passes through the aperture of the boss i Bland throughtheislotl I 4 (lithe bracket arm I i, and secures the bracket in adjusted position to K .the guard .8 :from which the. bracket depends, as

.l. illustrated iii-Fig. 1.

" M Asshown. in Fig. 5, the-.-bracketj lllcomprises a hollow cylindricaliguide. portionllfi in which a in. cylindrical member 1-6 isislidably mounted. This member. [Q has a .flat,-,bottomed, recess ll intone .i .side. thereof, and .theijivall of the cylinder. [5 is 501s1ottedat I8.-..for reception, of a barnlfi, which extends. intotithe. recess ll of \thetmember I 6 and forms a-stop limiting a the-longitudinal sliding movementof themember, l-6- inthecylinder l5. wjlhembarilB see Fig. 6 ,is secured to, the body of the cylinder l5 by means of screws 2i, and the inner face of the bar coacts with the fiat bottom of the recess IT to prevent the member l5 from turning about its axis in the cylinder l5. This bar also has a tapped hole 22 for reception of a thumb screw 23 which, when turned inwardly, bears against the flat bottom of the recess I1 and thereby acts to fix the member I 6 in adjusted position within the cylinder l5.

Attached to the top of the member 16 is a collar 24, this collar carrying athumb screw 25, the inner end of which engages in a circumferential slot 26 in the upper end of the member Hi.

This mode of attachment of the collar 24 to the provides further for fixing the collar in any required adjusted position upon the said member.

As shown in Figs. 5 and 8, a segmental plate 21 is attached by screws 28 to the upper end of the a member l6, and this plate projects outwardly The member l6 has a depending stem 3| which is threaded for reception of a knurled stop nut 32 and cooperating lock nut 33, and these nuts may be adjusted on the threaded stem to limit the extent of the upward move ment of the member l6 in the cylindrical guide l5 by engagement with the lower end'of the cylinder [5. Pivotally attached at the lower end of the bracket I2 is a lever 34 which extends through the bifurcated lower end of the stem 3| and is secured between said bifurcations by a split pin 35. By manipulation of the outer end of the lever 34, the member l6 may be elevated against gravity and lowered with gravity in the guide cylinder- [5.

The collar 24 has an upstanding bracket arm 36, see Fig. 7, and pivotally suspended against one face of this bracket arm 36 upon a projecting pin 31 is a slotted member 38 which constitutes a carrier for the toothed saw chain during the sharpening operation, as hereinafter described. The support member 38 is provided with a slot 39 extending inwardly from the under side thereof for reception of a set screw 4| which is threaded into a tapped hole 42 in the side of the bracket arm 36, this slot 39 being arranged so as to permit adjustment of the member 38 about the supporting pin 31 and to clamp the member 36 solidly against the bracket arm 36 in the selected position of adjustment. As shown in Fig. 1, the member 38 is provided at the top with a longitudinal slot 43, and this slot extends also to the curved ends of the said member. It will be noted by reference to Fig. 7 that the bracket arm 36 has marked thereon a scale 44 which functions to indicate the angularity of the member 38 with respect to the horizontal in various adjusted positions.

With reference again to Fig. 7, it will be noted that the bracket arm is provided with a slot 45, and secured to the face of the bracket arm by means of a .bolt 46 which extends through the slot 45 is a block 41. The bolt 46 passes through an aperture 48 in the block and is shaped to form a pivotal support for the latter. A wing nut 49 on the threaded end of the bolt 46 provides for ready release of. the bolt for adjustment in the slot 45. As shown in Fig. 10, the block 41 is provided with. 'a slot 5|, the open side of this slot in assembly being closed by the face of the bracket arm 35. Slidably supported in the slot 5! is a bar 52, one end of which projects into proximity to and directly above the member 38. To this end of the bar is attached a tip 53 having a transverse notch 54 in its end, the function of which will be hereinafter described. The other end of the bar 52 is offset downwardly and is provided with an aperture through which extends a rod 55 secured in and projecting from the end of the block 41. The rod 55 is threaded at its outer end for reception of an adjusting nut 56, and this nut bears against the outer end of the bar 52, as best shown in Fig. 4. Carried by the rod 55 is a coiled spring 51, and this spring is confined between the down-turned end of the bar 52 and a spring plate 53 also supported o the rod. 55 and bearing against the adjoining end surface of the bracket arm 36.

The spring plate 58 is shown in Fig. 11, and it will be noted that the plate is provided with an aperture 59 through which the rod 55 extends, and also with a recess 6| at its upper edge which provides for passage of the bar 52, all as shown in Fig. 9. This plate 58 not only finds a bearing against the end face of the bracket arm 36, but also against the corresponding face of the block 41. The spring plate 58 under pressure of the spring 51 exerts resilient pressure against the block 47, tending to retain this block in a position in which its outer face is flush or in parallel alignment with the adjoining end face of the bracket arm 36' against which the spring 58 bears, as previously set forth. This normal position of the block 41 is shown in Fig. l. The spring 51 also resiliently presses the extremity of the bar 52 against the inner face of the adjusting nut 56. It will be apparent that by manipulation of the nut 56 and the action of the spring 51, the bar 52 may be adjusted longitudinally in the slot 5! of the block 41.

As previously described, the spring 51 and spring plate 58 tend to retain the block 4'1 in a normal position, as shown in Fig. 1, wherein the bar 52 and the rod 55 will occupy the respective positions shown in broken lines in Fig. 4. The arrangement, however, permits movement of the block 4'! and of the associated parts around the pivot provided by the bolt 46, and this movement of the block 41 may be effected through the'mediurn of a handle 62 which extends downwardly from the under side of the said block. When this handle is turned to the left, as viewed in Fig. 4, the inner end of the bar 52, which carries the tip 53 as previously described, is depressed against the tension of the spring plate 58 toward the upper surface of the member 38.

The manner in which the member 38 functions to support the saw chain is illustrated in Figs. 4 and 12. As therein illustrated, the base projections 63 of the central links 64 of the chain fit snugly and slidably within the slot 43 of the support, while the fiat under surfaces 65 of the side links 66 of the chain bear upon the upper surface 67 of the member 38 at opposite sides of the slot 43. The chain is thus solidly supported and guided on the member 33, with the cutter teeth projecting upwardly toward the grinding wheel I. By elevating the member [6 through the medium of the lever 34 as previously described, the forward or cutting faces of the teeth may be brought into engagement with the abrasive wheel.

The bar 52 with its tip 53 functions to establish to the chain and to the lever 62 soas to hold the rear edge of a tooth under tension against the notched tip 53 of the index bar 52 to cause the tip 53 to bear down solidly upon the said rear edge of the tooth, the work is clamped securely to the carrier 38 in accurately indexed relationcorresponding tooth of the complete series is then similarly brought and held in proper position upon the carrier 38, and is presented to the grinding wheel by elevation of the member [6 through the medium of the lever 34. Differing teeth of the series may be similarly sharpened after adjustment of the various parts of the device in the manner described above to effect the proper presentation of the teeth to the sharpening tool.

It will be noted in the device described above that the upper portion of the work carrier 38, upon which the chain is supported for presentation to the grinding wheel I, is fiat, and that adjustment of the carrier in one plane is obtained by pivotal movement thereof about the pin 31. This arrangement is desirable, in that it simplifies adjustment of the carrier in said plane to the exact angular position with respectto the plane of the grinding wheel that will afford the required degree of hook in the chain teeth. The hook angle is clearly apparent to the eye and is indicated directly on the scale 44. Furthermore, since the sections of the chain immediately adjoining the tooth presented to the grinding tool are held straight and flat upon the carrier, there is no possibility that the tool may foul the proximate ends of the adjoining teeth, the clearance for the tool being constant in each setting of the carrier.

It is not essential, however, that the adjust ment of the carrier to regulate the hook angle shall be pivotal in character, since by employing a carrier of somewhat different form, the hook angle may be regulated as desired by a purely translational adjustment of the carrier in the given plane. A carrier of this character and its mode of adjustment is illustrated in Figs. 14 to 1'7, inclusive, wherein it will be noted that the work carrier 68 is curved at the top, the curve in the present instance describing the arc of a circle, and the flat base 69 of the carrier seats slidably upon the upper surface of the collar II which corresponds to the collar 24 of the previously described embodiment. The carrier 68 has a slot 12 which extends parallel to the flat base 59 of the carrier, and a clamping screw 13 extends through this slot and is threaded into the bracket arm '14, this arm being integral with or fixed to the collar H and corresponding to the arm 36 of the embodiment previously described. The screw 13 when tightened clamps the carrier 68 solidly against the proximate face of the arm 14, and when loosened permits adjustment of the carrier on its seat in the longitudinal direction to an extent limited: by the "length of the slot 12. The carrier 68 supports the toothed chain in the same general manner as the carrier 38 of the previously described embodiment, but

" in this instance the portion ofthe chain prethe upper surface of the carrier 68 upon which the chain seats.

It will be apparent that with this arrangement any adjustment of the carrier on its seat as described above will change the angle at which the supported chain is presented to the grinding tool. This is illustrated, for example, in Fig. 15, which shows the carrier in a different position of adjustment than that shown in Fig. 14. It will be noted that the front or cutting face of the tooth which occupies a position on the carrier immediately below the grinding wheel 1 in Fig. 15 bears a different angular relation to the plane of the face of the wheel than the face of the chain tooth occupying a corresponding relative position in Fig. 14. By adjustment of the carrier 68, therefore, the hooks of the teeth may be ground to any required angle. The adjustment of the carrier 68 occurs in the same relative plane as that of the carrier 38 of the previously described embodiment, but is translational in character rather than pivotal.

An indexing scale indicated by the reference numeral 15 is provided on the carrier 68 to facilitate adjustment of the carrier and of the chain on the carrier into position to afford the correct hook angle. The datum point for the empirical scale 15 may be selected on any point on the base of the tooth, for example the point marked A on Fig. 14. For adjustment of the collar H. about the axis of the cylindrical member 16, an index scale is provided on the side of the said collar, as indicated at '16, this scale being related to the relatively fixed datum point Ti on the side of the guide cylinder I5. In all other respects and with the exception of the form and mode of adjustment of the carrier 68, the device may correspond to that illustrated in Figs. 1 to 13, inclusive.

It will be apparent that the curved work seat of the carrier 68 need not necessarily take the form of a circular arc, and that the work carrier, in fact, may take various forms other than that shown in the two aforedescribed embodiments of the invention. It will be apparent also that the adjustment of the carrier in the one plane may Without departure from the invention be effected by a combination of translational and pivotal movements.

While, for purpose of specific illustration, the device has been described in conjunction with an electric grinder of conventional commercial type, it is apparent that the device is not restricted to use with any particular form of grinding mechanism or character of sharpening tool, and

. that there may be considerable modification in the form of the device and the relative arrangement of the component parts without departure from the invention as hereinafter defined.

I claim:

1. The combination with a support structure, of a tool mounted in said support for rotation in a predetermined plane, a member guided in said support for longitudinal reciprocation along a path intersecting at right angles the axis of rotation of said tool, a work carrier mounted on said member, means for adjusting said carrier relative to the member and said member relative to the support, each angularly with respect to the plane of said tool, means for clamping the work on the carrier by manual pressure, said means comprising an abutment for indexing the work with respect to the tool, and an actuator for said indexingand clamping means arranged so that one hand of the operatormay simultanetool,smeans for traversing said memberin the I guide, adjustable means forilimiting said traverse movement ,innthe directionof' the tool, means for clamping the work on thecarrier by manual pressure, said means comprisingan-abut ment for indexingthe workwith=respect to the tool, and vanactuator for saidindexing -ancl clamping means arranged so that one hand of the operator may simultaneously retain the work in pressure engagement with said abutment and actuate said means-to exert. clamping pressure onthework.-

3. The combination with a support structure, of a tool mounted in-isaidisupport' fonrotation-in a predetermined plane, a member guided in -said support for longitudinal reciprocation: alonga path intersecting; at ,right angles; the axis of --rotation of said tool,-.a work lcarrier'mounted on saidmember; means for :adjusting; said carrier on said member with respectto the plane of the tool, means or traversingzsaid member in the guide, means for limitingthe traverse movement,

releasable means for immobilizing said member in the. guidein any desired" position in the-path of said traverse, meansicr clamping the-workon the carrier 'by manual pressure, 'said means comprising anabutment ;for indexing the i work with respect to the tool, and'anractuatorjor said indexing and clamping means arranged so thatone hand of the operator may simultaneously retain the work in pressure engagement with said abutment and actuate said'means to exertclamping pressure on the-work.

4. The combination with a support structure, of a tool mounted in said structure, 2a member mounted in said structure-for movement to and from the tool, a work carrier on :said member, and means on said memberrfor positioningthe work on its carrierwith respect to the tool, saidtive to retain said pivoted: element resiliently in.

a"predeterminediangular' position on its pivot while permitting oscillation of said pivoted element to rtraverse'.thawork-engaging element withrespect'to the carrier.

-5."The combination with a support structure, of a toolz'mounted insaid support for movement in a predetermined: plane, a work carrier guided in said support for movement with respect to said tool-,asaidparrier having astraight seat'adapted to support-iatoothedchain in a rectilinear line intersecting the plane of said tool for presenta tion to the latter, and means for pivotally" adjusting said carrier in the supportin a plurality of planes intersecting the plane of said'tool', one ofsaid planes of adjustment including said rectilinear line. I g

6-. The combination with a support structure, of a tool mounted in said support for movement in a predetermined plane, a work carrier guided in said support for movement with respectto said tool, said carrier having a straight seat adapted to support a toothed chain in a rectilinear line intersecting the plane of said tool for presentation to the latter, and means for pivotallyadjusting said carrier in the support in each of two 1 planes intersecting the plane of said tooland at right angles to each other, one atleast of said two planes of adjustment being at right angles to the plane of the tool.

7. The combination with a support structure,

2 of a tool mounted in said support for rotation in a predetermined plane, a work carrier guided in said support for reciprocation along a path intersecting at right angles the axisof rotation of said tool, means for angularly adjusting said carrier in the support in a plurality of planes intersecting the plane of said tool to thereby vary the angular position of the work with respect to the last-named plana'means for clamping the work on the carrier by manual pressure, said means comprising an abutment for indexing the work with respect to the tool, and an-actuator for said indexing and clamping means arranged so that one handof the operator may simultaneously adjust the work-and actuate-said means to i, index and clamp the Work on the carrier.

8. The combination with a support structure, of a tool mounted in said support-forrotation in a predetermined plane, a work carrier guided in said support for reciprocation along a path in tersecting at right angles the axis of rotation of said tool, means for angularly adjusting said car rier in thesupport in-eachof two planes intersecting the plane of said tool and at rightang-les to each other to thereby vary the angular position of thewvorkwithrespect to the last named plane meansfor clamping the work on the car-- rier by manual pressure, said-means cemprising an abutmentv for indexing the work-with;respect to the, tool, and an actuator for said-indexing-and clamping means arranged so that one hand of the operator may simultaneously adjust the: work and actuate said means to index and clamp the work onthe carrier.-

- 9. .The combination with a support structure,

of a tool mounted in said;supportforrotation in a predetermined plane, a Workcarrier guided in said support for reciprocation along a path in tersecting at right angles theaxis of rotatipnpf saidtoohmeans for angular-ly-adjusting said carrierin the support ineachpi-two planes intersecting the plane of said tool and at right angles to each other, one at least'of said two planes of adjustment being at right angles toth planeoi, the toohmeans for clamping the work onthe c are rier by manual pressure, said means comprising an abutment for indexing the Work with respect to the tool, and anactuator for said indexing and clampingmeans-arranged sothat one: hand of the operator may simultaneously adjust thefvvork and actuate said means-to indexand clamp the work-on the carrier.-- [I I vi 10. The'combination with a support structure, of a shaft journaled in said structuraa grinding wheelon the shaft, awork support mountedon said structure for angular adjustment as a whole about the axis of said shaft as a center, a member guided in said work support for longitudinal reciprocation along a path intersecting at right angles the said shaft axis, and a work carrier mounted on said member for angular adjustment in a plurality of difierent planes with respect to the plane of rotation of said wheel.

11. The combination with a support structure, of a tool mounted in said support for movement in a predetermined plane, a work carrier guided in said support for movement with respect to said tool, said carrier having a straight seat adapted to support a toothed chain in a rectilinear line intersecting the plane of said tool for presentation to the latter, and means for pivotally adjusting said carrier in the support in each of two planes intersecting the plane of said tool and at right angles to each other.

12. A cutting chain sharpener having in combination a sharpening wheel, a reciprocating member arranged so that it can be reciprocated by one hand of the operator, a second member rotatably adjustable on the said reciprocating member, a chain carrier adjustably attached to said second member and having a runway for support of said chain, an element having an oscillating indexing and clamping abutment for said chain and arranged so that the other hand of the operator may progressively index the chain along said runway and then simultaneously actuate said element to engage the chain, hold the chain in pressure engagement with the element, and clamp the chain to said runway.

13. A cutting chain sharpener as defined in claim 12, wherein the work carrier has a straight runway adapted to support the toothed chain in a rectilineal line.

1%. A cutting chain sharpener as defined in claim 12, wherein the said element which is adapted to engage and disengage the toothed chain has micrometrically adjustable means for precise indexing of the chain with respect to the sharpening wheel.

15. A cutting chain sharpener as defined in claim 12, wherein a guard embraces said sharpening wheel and is angularly adjustable about its axis, and that the said reciprocating member is guided in a support structure adjustably attached to said uard.

16. A cutting chain sharpener as defined in claim 12, wherein the center line of said reciproeating member, the axis of rotation of said second member, the path of oscillation of the indexing abutment of said element, are all parallelly adjacent to, or substantially coincide with the path traced by the work at the points of contact with the sharpening wheel.

1'7. The combination with a support structure, of a tool mounted in said structure for rotation in a predetermined plane, a work carrier guided in said support for radial reciprocation with respect to the tool, means for traversing the carrier in the guide, a combined stop and clamping element for indexing the work with respect to the tool and for clamping the work in indexed position upon the carrier, and an actuator for said element arranged so that one hand of an operator may simultaneously manipulate the element and the work so as to move the work on the carrier into pressure engagement with the stop and, while retaining said engagement, actuate the stop to clamp the work on the carrier.

18. The combination with a support structure, of a tool mounted in said structure for rotation in a predetermined plane, a Work carrier mounted in said structure and having means for guiding the work for adjustment with respect to the tool, means for adjusting the carrier in a plurality of planes to vary the angular position of the work with respect to the plane of the tool means for relatively reciprocating said tool and carrier with respect to each other in a direction radially of the tool, a combined stop and clamping element for indexing the work with respect to the tool and for clamping the work in the carrier guide in the indexed position, and an actuator for said indexing and clamping element arranged so that one hand of an operator may simultaneously manipulate the element and the work so as to move the work on the carrier into pressure engagement with the stop and, while retaining said engagement, actuate the stop to clamp the work on the carrier.

19. The combination with a support structure, of a tool mounted in said structure for rotation in a predetermined plane, a work carrier mounted said structure, means for adjusting the carrier in a plurality of planes to vary the angular position of the carrier with respect to the plane of the tool, means for relatively reciprocating said tool and carrier with respect to each other in a direction radially of the tool, a combined stop and clamping element movable to and from the carrier in one of said planes of adjustment for indexing the work with respect to the tool and for clamping the work in the indexed position on the carrier, and an actuator for said indexing and clamping element arranged so that one hand of an operator may simultaneously manipulate the element and the work so as to move the work on the carrier into pressure engagement with the stop and, while retaining said engagement, actuate the stop to clamp the work on the carrier.

20. The combination with a support structure, of a grinding wheel mounted in said structure for rotation in a predetermined plane, a work carrier mounted in said structure for manual reciprocation on a line substantially radial to the wheel, means for positioning the work on the carrler and for clamping the work in position durng the grinding operation, said means comprismg a combined stop and clamping element and a support for the element relatively fixed with respect to the carrier, said element being guided by said support for manual actuation to engage the work on the carrier, means operative independently of the movements of the work carrier for normally retaining the element in a retracted position with respect to the work, and. means arranged so that one hand of an operator may advance the stop, may move the work on the carrier into pressure engagement with the stop, and while retaining said pressure engagement may actuate the said stop to clamp the work on the carrier.

21. The combination with a support structure, of a grinding wheel mounted in said structure for rotation in a predetermined plane, a work carrier mounted in said structure for manual reciprocation on a line substantially radial to the wheel, means for positioning the work on the carrier and for clamping the work in position during the grinding operation, said means comprising a combined stop and clamping element mounted for oscillation on a pivot relatively fixed with respect to the carrier'and adapted in operative positions to predeterminedly locate the work on the carrier with respect to the tool and to clamp the work in said predetermined position, means operative independently of the movements of the work carrier for normally retaining said element in retracted position with respect to the work, and an actuator for said element arranged so that one hand of the operator may simultaneously manipulate the element and the Work so as to move the work on r the carrier into pressure engagement with the stop and, while retaining said engagement, actuate the stop to clamp the work on the carrier.

- 22. The combination with a support structure, of a grinding wheel mounted in said structure for rotation in a predetermined plane, a work carrier mounted in said structure for manual reciprocation on a line substantially radial to the Wheel, said carrier having a work receiving slot in which the work is freely guided for adjustment on the carrier in a path transverse to the plane of the tool, means for locating the work in a predetermined position of adjustment longitudinally of the slot and for clamping the work in the adjusted position in the carrier, said means comprising a combined stop and clamping element mounted on a pivot relatively fixed with respect to the carrier for oscillation in the plane of said slot, means for traversing the carrier radially with respect to the wheel, and an actuating lever for said locating and clamping element extending in proximity to said carrier so that one hand of an operator may simultaneously manipulate the element and the work so as to move the work on the carrier into pressure engagement with the stop and, while retaining said engagement, actuate the stop to clamp the work' on the carrier.

23. The combination with a support structure, of a grinding wheel mounted in said structure for rotation in a predetermined plane, a work carrier mounted in said structure for reciprocation on a line substantially radial to the Wheel, said carrier having a work receiving slot in which the said work is freely guided for adjustment in a path transverse to the plane of the tool, means for locating the work in predetermined position longitudinally of said slot and for clamping the work to the carrier in said position, said means comprising a combined stop and clamping element mounted on a pivot relatively fixed with respect to the carrier for oscillation in the plane of said slot, an operating lever for said element taining said engagement, actuate the stop to' clamp the work on the carrier.

24. The combination with a support structure, of a grinding wheel mounted in said structure for rotation in a predetermined plane, a work carrier mounted in said structure for reciprocation on I a line substantially radial to the wheel, said carrier having a work receiving slot in which the said work is freely guided for adjustment in a path transverse with the plane of the tool, means for locating the work in predetermined position longitudinally of said slot and for clamping the work in said position, said means comprising a combined stop and clamping element mounted on a pivot relatively fixed with respect to the carrier for oscillation in the plane of said slot, means for adjusting said element longitudinally of the slot, an actuator for said element extending in proximity to the carrier whereby one hand of an operator may simultaneously manipulate the element and the work so as to move the work on the carrier into pressure engagement with the stop and, while retaining said engagement, actuate the stop to clamp the work on the carrier.

25. The combination with a support structure, of a grinding wheel mounted in said structure for rotation in a "predetermined plane, a work carrier mounted in said structure for manual reciprocation on a line substantially radial to the wheel, stop-and-clamping means for holding the work in position during the grinding operation, means operatively independent of the movements of the work carrier for retracting the said stop-and-clamping means from the work after the grinding operation so as to free the work for manual adjustment toa new position on the carrier, and means arranged so that one hand of an operator may simultaneously manipulate the stop means and the Work so as to move the work on the carrier into pressure engagement with the stop and, while retaining said engagement, actuate the stop to clamp the work on the carrier.

ARTHUR N. BLUM. 

